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     Geant4 - an Object-Oriented Toolkit for Physics Simulation
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          History file for hadronic/models/de_excitation
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This file should be used to summarize modifications introduced in the 
code and to keep track of all tags.

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     * Please list in reverse chronological order (last date on top)
     ---------------------------------------------------------------

13-February 2009 V.Ivanchenko   hadr-pre-V09-01-16
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G4PreCompoundXXX - add decrease Coulomb barrier for d, t, a, he3 (JMQ)

10-February 2009 V.Ivanchenko
-----------------------------
Some clean up of comments
G4PreCompoundIon - fixed probability of light ion emmision (JMQ)

09-December 2008 A.Howard   hadr-pre-V09-01-15
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Added protection for close to zero excitation energy in 
G4PreCompoundModel.cc (according to JMQ, MAC) to not try to de-excite.

09-December 2008 A.Howard   hadr-pre-V09-01-14
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Added protection for close to zero excitation energy in 
G4PreCompoundTransitions.cc (returns 0.0), prevents FPE later on.

27-November 2008 A.Howard   hadr-pre-V09-01-13
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Added data member initialisation to G4VPreCompoundTransitions.hh

19-November 2008 A.Howard   hadr-pre-V09-01-12
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JMQ fix to G4PreCompoundNeutron.cc for Zirconium (if (nu < 0.)nu=-nu).

30-September 2008 A.Howard   hadr-pre-V09-01-11
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Trivial protection against negative probabilities for incident protons on
targets with A < Carbon.

22-September 2008 A.Howard   hadr-pre-V09-01-10
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JMQ's latest developments - which are an extension of hadr-pre-V09-01-08 with
cross-section options (equivalent to the de-excitation modifications) and other
options (SICB, Never Go Back,...).  In addition Gunter's fix to the factorials
is included from hadr-pre-V09-01-09.
Added new files: G4PreCompoundAlpha.cc G4PreCompoundDeuteron.cc
G4PreCompoundHe3.cc G4PreCompoundNeutron.cc G4PreCompoundProton.cc
G4PreCompoundTriton.cc (Classes previously existed.  Now they have more 
involved cross-section calculations).

19-September 2008 A.Howard   hadr-pre-V09-01-09
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Including Gunter's fix (see 11-August below) on top of ref-07 
(hadr-pre-V09-00-04), i.e. without JMQ's developments.

11-August 2008 G.Folger      
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Rewrite algorithm in G4PreCompoundEmission::rho() to avoid frequent 
floating point overflow when using Precompund in combination 
with Binary Cascade. 


24 July 2008 J. M. Quesada   hadr-pre-V09-01-08
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Minor fixes and Coulomb barrier just for Wellisch's proton cross section 
(OPT=2) 


23 July 2008 V.Ivanchenko    hadr-pre-V09-01-07
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Fixed mistake in tagging

23 July 2008 V.Ivanchenko    hadr-pre-V09-01-06
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Return back Coulomb barrier initialisation (J.M.Quesada)

27 June 2008 V.Ivanchenko    hadr-pre-V09-01-05
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Fixed G4PreCompoundNucleon and G4PreCompoundIon for
Coulomb barrier, added protections for zero cross sections,
OPT=2 is used (J.M.Quesada)

05 June 2008 J. M. Quesada   hadr-pre-V09-01-04
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Bug fixed in OPT=1 (Chatterjee) charged particle cross sections.
Unphysical values at very low emission energies have been corrected (set
to 0); OPT=1 ( OPT=2 in previous tag)


15-May 2008 J. M.Quesada     hadr-pre-V09-01-03
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The retrieval of transition probabilities in G4PreCompoundModel.cc 
(for protection against unphysically crossing the landa_+=landa_- condition) 
was misplaced.  Now it has been placed inside the preequilibrium transitions 
loop. 

8-May 2008 J. M.Quesada     hadr-pre-V09-01-02
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Protection against non physical situation has been set: Equilibrium exciton number 
Neq (when reached, equilibrium regime starts) should correspond to equal transition 
probabilities "back" and "forth". Nevertheless,  for heavy target (Neq is big even 
for low incident energies) after first emission this condition (equal trans. prob.) 
is reached far before reaching corresponding Neq of the residual. Unless this "jump" 
to equilibrium is forced in this case, preequilibrium will be 
spuriously prolonged (as a side effect, with huge CPU consumption).  
G4PreCompoundModel and G4PreCompoundTransitions classes have been modified.


1-May 2008 J. M.Quesada     hadr-pre-V09-01-01
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- First trial with cvs. 00 skipped by mistake. 
New inverse cross sections:
        OPT=1 Chetterjee's parameterization to reaction cross sections from optical potential global fittings.
        OPT=2 as OPT=1 but for protons the Wellisch's parameterization for protons is used  (DEFAULT)
        OPT=3 Kalbach's modifications of Chatterjee's parameterization of cross sections
        OPT=4 as OPT=3 but for protons the Wellisch's parameterization for protons is used

Coulomb barrier has been suppressed as it enters through inverse cross sections. Also methods related to former Dostrovski's cross sections (alpha , beta and C parameters) have been suppressed. In all particle header files: 
G4PreCompoundNucleon.hh ,G4PreCompoundNeutron.hh,G4PreCompoundProton.hh, G4PreCompoundIon.hh, G4PreCompoundDeuteron.hh, G4PreCompoundTriton.hh ,G4PreCompoundHe3.hh , G4PreCompoundAlpha.hh


Soft cutoff transition from equilibrium to equilibrium has been suppressed (unphysical and not necessary anymore).In G4PreCompoundModel. 

New transition probabilities :
        OPT=1  Gudima's formulae
        OPT=2  Machner parameterization of matrix elements for transitions (DEFAULT)
  
Level density is set to A/10 (Gudima's prescription). 

Several bugs fixed (average xs in nucleon-nucleon xs in G4PreCompundTransitions.cc and  emission probability formula in G4PreCompoundIon.cc ) .  

25-October 2007 A.Howard     hadr-pre-V09-00-04
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- Removed compilation warning on unused parameter in G4PreCompoundIon.cc


11-October 2007 A.Howard     hadr-pre-V09-00-03
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- Corrected for integer arithmetic bug in G4PreCompoundModel.cc 
  (ratio of charged to neutral excitons)


01-October 2007 A.Howard     hadr-pre-V09-00-02
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- Protected Rj (Q_beta) factor against divide by zeroes (should never happen?)
  The following files have been modified:
  G4PreCompoundAlpha.hh, G4PreCompoundDeuteron.hh, G4PreCompoundHe3.hh, 
  G4PreCompoundTriton.hh, G4PreCompoundNeutron.hh, G4PreCompoundProton.hh
  

23-August 2007 A.Howard     hadr-pre-V09-00-01
----------------------------------------------
- Development tag incorporating further suggestions/corrections from 
  Jose-Manuel Quesada particularly with respect to light ion production. 
  The following files have been modified:
  G4PreCompoundIon.cc, G4PreCompoundDeuteron.hh, G4PreCompoundHe3.hh,
  G4PreCompoundTriton.hh, G4PreCompoundAlpha.hh, G4PreCompoundIon.hh,
  G4VPreCompoundIon.hh (unused?)


23-July 2007 A.Howard       hadr-pre-V09-00-00
----------------------------------------------
- Development tag incorporating the suggestions/corrections of Jose-Manuel
  Quesada.  These should reflect the literature and units expected for the
  exciton model.  The following files have been modified:
  G4PreCompoundNucleon.hh, G4VPreCompoundNucleon.hh, G4PreCompoundAlpha.hh,
  G4PreCompoundHe3.hh, G4PreCompoundDeuteron.hh, G4PreCompoundNeutron.hh,
  G4PreCompoundProton.hh, G4PreCompoundTriton.hh
  G4VPreCompoundIon.cc, G4PreCompoundIon.cc, G4PreCompoundModel.cc,
  G4VPreCompoundFragment.cc, G4PreCompoundTransitions.cc,
  G4PreCompoundNucleon.cc, G4VPreCompoundNucleon.cc
  The main changes are:
  - introducing an Rj factor into the probability calculation, 
  - correcting the units for the Pauli Blocking Factor - missing a g factor,
  - decreasing the number of charged particles if the number excitons is
    decreased (previously this number was only increased with increasing
    excitons).


04-May 2007 G.Folger       hadr-pre-V08-02-00
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-  G4PreCompoundTransitions.cc: Protect against divide by 0

19 Aug 2006 Dennis Wright (hadr-pre-V08-01-00)
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- exciton_model
   G4VPreCompoundFragment.hh, .icc : remove meaningless const from 
   methods GetA, GetZ, GetRestA, GetRestZ, GetCoulombBarrier, GetBindingEnergy,
   GetMaximalKineticEnergy, GetEnergyThreshold, GetEmissionProbability, 
   GetNuclearMass, GetRestNuclearMass and GetReducedMass

